Documents are known in which the problem of measuring the conditions of the wheels of railway vehicles has been addressed. Thus, Patent Application ES P9501305 describes an installation and a procedure for measuring running parameters on the wheels of railway vehicles, in which use is made of laser generators and cameras for obtaining images corresponding to the profile or to the diameter of a wheel, these images being sent to analytical equipment and the results of the analysis being transmitted to a computer for processing and display on a monitor; Patent EP-A-0 467 984 describes an installation for detecting the profile of train wheels using an illumination unit, a probe unit, a measuring unit and a data processor; and Patent JP-A-06-123608 describes a device for measuring wheels by forming images corresponding to the shape of the surface of the running tread and of the inner face of the wheels and by calculating, on the basis of these images, the shape of the surface of the running tread and the diameter of the wheels.